USBTMC stands for USB Test & Measurement Class. Any USB device conforms to USBTMC without the limitations of operation systems and environment can work under VISA assistance, and communicate with a computer.In other words, the control procedures via VISA to USBTMC device and via VISA to GPIB device are the same.

The advantage of using USBTMC with M3500A is that you dont have to buy any expensive GPIB module, and waste time to re-program the previous application software which is for GPIB. Only the instruments conform to USBTMC protocol in the VISA basis, and the version of NI-VISA 3.1 or upward driver is installed. The USBTMC unit under the original GPIB software will be recognized, and can be easily used. Besides, it also offers users other benefits, for example, support 127 DMM connections at a time, USB cord can work with a long distance application (at most 30M), and it is easy to get the cord. (For more detail USBTMC information,please click here [Q.What is USBTMC? ].

USBTMC Application Note:
Before using USBTMC, please click into NI website www.ni.com - NI-VISA to download NI driver. After setting up M3500A application software, PT-TOOL & PT-LINK (enclosed in the CD), or your own programs, the M3500A will be controlled easily.

The 6 1/2 digit M3500A DMM is designed with 71/2 digit techniques to provide user a stable, faster and accurate measurement. The following figure is the stability performance comparison between the typical 61/2 digit DMM and the M3500A .

High Speed:2000 Readings / Sec

The M3500A is engineered with expertise to reach such a high performance: both of the sampling rate and the data transfer rate can achieve 2000 readings per second.

Our thermal measurement functions support two types of measurements: Thermocouples and RTDs. For thermocouples, we support up to seven types of sensors: J, K, T, E, N, S and R, using a NIST Monograph 175 reference table. Moreover, for the RTDs temperature conversions, we adopt three types of standard: ITS-90, IEC751 and Callendar-Van Dusen standard in our thermal measurement functions. All these are made for user's convenience

Multi-Point Scan

The M3500A supports some (2-pole) multi-point scanner cards, such as OPT01, OPT09, and OPT12. OPT01(10CH)/OPT09 (20CH) are used for general purpose measurements including DCV/ACV/Indirect DCI & ACI with Current Shunt/2W/4W/Freq./Period. OPT12 (10CH) provides not only the mentioned measurements, but also thermocouple and RTD applications. The installation of the multi-point scanner cards are very easy - just turn the power off and plug in the multi-point scanner card, and it is done!

Dual Displays with 3-Color Annunciators

This model comes with a unique 5x7 dot matrix, VFD dual displays with three-color annunciators. User can easily distinguish each symbols by their colors.

This model has an excellent performance on noise immunity. The core of this DMM is a powerful multi-slope analog to digital converter (A/D converter) This special A/D converter (p.s. patent is pending) helps the DMM to reach high-speed sampling rate, filters out most noise, and still keeps a good measurement linearity. In addition, to reduce the environmental background noise, we have added four sets of earth ground on the meter's front panel. And the copper conductors inside the meter also contribute to reducing thermal EMFs.

Built-in USB Interface

The M3500A Series is equipped with a standard USB interface. This easy-to-use and hot plug-in USB interface has a high data-transfer rate over 2000 readings per second. It allows your DMM to reach a truly high speed, both internal sampling rate and I/O data rate, thus increase the measurement speed of your DMM.

The Remote-Control Software, PT-TOOL & PT-LINK, is free and easy for user’s application. PT-TOOL is a stand-alone software which can imitate virtual M3500A operations on the PC, and allow users to transmit data in Excel format. In addition, PT-LINK under the Microsoft Word & Excel application provides users a simple function of getting values and diagrams.